Sorry, yes, even a little. Why? Because studies have found that even as little as 1 teaspoon can impair your immune system by 50 percent for up to a few hours after consumption. This occurs because refined sugar reduces the functioning of white blood cells, which are required to help the body defend itself against infection. Refined sugar means anything white— white sugar, white flour, cookies, candy, energy drinks, cake, and even processed orange juice. That is correct, drinking orange juice when you are sick actually makes things worse. Instead of sugar, try using sweeteners like stevia or xylitol, which have a lower glycemic index and do not wreak such havoc on the immune system as “the whites” do.